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Old 09-22-2018, 10:59 AM
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Default Testing props

Posted in the prop section as well..

So factory labbed 28 Bravos I get the rpms Im after but not the mph. Factory labbed 30 Bravo is faster but not getting the rpm I need for peak HP. Like 400 tpms from where need to be.. Ideas? Which ones should I have dialed in for my boat.
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Old 09-22-2018, 11:41 AM
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Have the 28s cupped for more bite, might lower rpm a little but not nearly as much as the 30s.
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Old 09-23-2018, 08:16 AM
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Im leaning toward working the 30s more being they are faster than the 28s even thought the rpms are lower than I need. If I can get more rpms out of the 30s I should be good. Just dont think working the 28s will give me the speed . Already turning the 28s hard enough bit the mph isn't there.
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Old 09-23-2018, 05:31 PM
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Should be able to thin and sharpen the 30s for more rpm but keep the same pitch. In theory may result in more rpm and more speed
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Old 09-23-2018, 06:08 PM
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Kinda what I was thinking. That and cut the diffuser off
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Old 09-23-2018, 11:57 PM
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I'd be careful about cutting off the diffuser ring. Not that much to be gained and could make planing much harder.
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Old 09-24-2018, 01:07 PM
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Originally Posted by Griff View Post
I'd be careful about cutting off the diffuser ring. Not that much to be gained and could make planing much harder.
Ive done it on a set of labbed 30s and it did pick up about 100 rpms. 1 to 1.5 mph and allowed then to blow out a little right where I needed it. They had no blow out before, just enough blow out now to take the stress off the drives. Cut 1/2 in off.
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